Files
Seele/src/Engine/Component/AABB.h
T
2022-11-29 16:34:42 +01:00

105 lines
3.2 KiB
C++

#pragma once
#include "Math/Vector.h"
#include "Math/Matrix.h"
#include "Containers/Array.h"
namespace Seele
{
struct AABB
{
Math::Vector min = Math::Vector(std::numeric_limits<float>::max());
Math::Vector max = Math::Vector(std::numeric_limits<float>::min());
float surfaceArea() const
{
Math::Vector d = max - min;
return 2.0f * (d.x * d.y + d.y * d.z + d.z * d.x);
}
bool intersects(const AABB& other) const
{
if (min.x > other.max.x
|| max.x < other.min.x)
{
return false;
}
if (min.y > other.max.y
|| max.y < other.min.y)
{
return false;
}
if (min.z > other.max.z
|| max.z < other.min.z)
{
return false;
}
return true;
}
bool contains(const AABB& other) const
{
if (min.x > other.min.x
|| max.x < other.max.x)
{
return false;
}
if (min.y > other.min.y
|| max.y < other.max.y)
{
return false;
}
if (min.z > other.min.z
|| max.z < other.max.z)
{
return false;
}
return true;
}
AABB getTransformedBox(const Math::Matrix4& matrix) const
{
StaticArray<Math::Vector, 8> corners;
corners[0] = Math::Vector(min.x, min.y, min.z);
corners[1] = Math::Vector(min.x, min.y, max.z);
corners[2] = Math::Vector(min.x, max.y, min.z);
corners[3] = Math::Vector(min.x, max.y, max.z);
corners[4] = Math::Vector(max.x, min.y, min.z);
corners[5] = Math::Vector(max.x, min.y, max.z);
corners[6] = Math::Vector(max.x, max.y, min.z);
corners[7] = Math::Vector(max.x, max.y, max.z);
Math::Vector tmin = Math::Vector(1, 1, 1) * std::numeric_limits<float>::max();
Math::Vector tmax = Math::Vector(1, 1, 1) * std::numeric_limits<float>::min();
for(int i = 0; i < 8; ++i)
{
Math::Vector transformed = matrix * Math::Vector4(corners[i], 1.0f);
tmin = Math::Vector(std::min(tmin.x, transformed.x), std::min(tmin.y, transformed.y), std::min(tmin.z, transformed.z));
tmax = Math::Vector(std::max(tmax.x, transformed.x), std::max(tmax.y, transformed.y), std::max(tmax.z, transformed.z));
}
return AABB {
.min = tmin,
.max = tmax,
};
}
void adjust(const Math::Vector vertex)
{
min.x = std::min(min.x, vertex.x);
min.y = std::min(min.y, vertex.y);
min.z = std::min(min.z, vertex.z);
max.x = std::max(max.x, vertex.x);
max.y = std::max(max.y, vertex.y);
max.z = std::max(max.z, vertex.z);
}
AABB combine(const AABB& other) const
{
return AABB {
.min = Math::Vector(
std::min(min.x, other.min.x),
std::min(min.y, other.min.y),
std::min(min.z, other.min.z)
),
.max = Math::Vector (
std::max(max.x, other.max.x),
std::max(max.y, other.max.y),
std::max(max.z, other.max.z)
),
};
}
};
} // namespace Seele